The present invention relates generally to a communications bus, and more particularly, to apparatus for diagnosing a communications bus.
Many different forms of communications busses exist. Typically a communications bus is formed to permit several devices to send and receive data from the other devices. Many different types of data protocols are available for transmitting information over a data bus. Those protocols are dependent, to some extent, on the hardware characteristics of the bus and the types of devices that will be connected to the bus.
Although known communications buses work satisfactorily, they require dedicated test equipment to diagnose malfunctions in the communications. The equipment must be connected to the bus, the malfunction diagnosed, the problem corrected and the equipment removed from the bus. Sometimes the test equipment and service technicians are located a long distance from the communications bus to be tested. It would therefore be preferable to have a communications bus that was capable of self diagnoses and could display a suggested solution to the end user, preferably without the use of dedicated test equipment and service technicians.
In one aspect of the present invention, a method of operating a communications bus in a diagnostics mode is disclosed. The communications bus is generally connected with a plurality of devices, each of the devices having a transmitting and a receiving subsystem. The diagnostics mode includes transmitting a known data pattern on said communications bus, receiving data corresponding to the transmitted data, comparing the received data to the transmitted data, and producing a diagnostics indication as a result of said comparison.
These and other aspects and advantages associated with the present invention will become apparent to those skilled in the art upon reading the following detailed description of the preferred embodiment in connection with the claims and drawings.